Journal articles on the topic 'Aquatic insects – alaska – identification'
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1
Francis, Tessa B., Daniel E. Schindler, and Jonathan W. Moore. "Aquatic insects play a minor role in dispersing salmon-derived nutrients into riparian forests in southwestern Alaska." Canadian Journal of Fisheries and Aquatic Sciences 63, no. 11 (November 1, 2006): 2543–52. http://dx.doi.org/10.1139/f06-144.
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Recent research has highlighted the importance of nutrients derived from Pacific salmon (Oncorhynchus spp.) carcasses for coastal freshwater and riparian ecosystems. To investigate the role of emerging aquatic insects in dispersing salmon nutrients from spawning streams to riparian habitats, we quantified the emergence and return rates of mayflies (Ephemeroptera), stoneflies (Plecoptera), and caddisflies (Trichoptera) on Pick Creek in southwestern Alaska and, using stable isotopes, estimated the associated flux of nutrients derived from sockeye salmon (Oncorhynchus nerka) to streamside forests. Between June and September of 2004, 7.6 mg·m–2 of salmon-derived nitrogen emerged from Pick Creek in the form of aquatic invertebrates, 6.7 mg·m–2 of which was transferred to the terrestrial ecosystem. Dispersal patterns on four area streams showed that the majority of stream-borne nutrients are deposited within 25 m of the stream. Aquatic insects represent a minor vector for salmon nutrients to terrestrial systems, dispersing less than 0.03% of total nitrogen imported to Pick Creek by spawning salmon. Nevertheless, emerging insects make available salmon-derived resources otherwise inaccessible to some terrestrial consumers.
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Badanaro, Fegbawe, Pelei Tagba, and Mamatchi Melila. "Aquatic Insects Consumed in Togo: Diversity and Nutritional Potential." European Journal of Nutrition & Food Safety 16, no. 7 (July 4, 2024): 336–47. http://dx.doi.org/10.9734/ejnfs/2024/v16i71484.
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This study identified the species of aquatic insects consumed in Togo, and determined the chemical composition of the most common species (Cybister tripunctatus (Sharp, 1882) (Coleoptera: Dytiscidae)). This was achieved through ethnoentomological surveys and species identification at the insectarium of the University of Lomé and it provided information on aquatic insects consumed in Togo. Samples of C. tripunctatus were collected in the three localities where ethnoentomological surveys were carried out. Ash, protein, vitamin and lipid contents were determined according to AOAC reference methods. Fiber content was determined using the Weende method. Minerals were analyzed by atomic absorption spectrophotometry and colorimetry. Lipid composition in fatty acids was determined by gas chromatography, and protein composition in amino acids was determined by separation of amino acids using the Biochrom 30+ analyzer. Forty-five out of 120 people interviewed from the Moba ethnic group said they occasionally consumed adult dytics. Four species consumed by this aborigine population was identified. None of these species is sold commercially. According to the respondents, the consumption of dytics is motivated by their nutritional and therapeutic virtues. C. tripunctatus consists of 10.32% moisture, 36.52% proteins, 26.98% lipids, 12.60% fibers, 4.94% carbohydrates, and has an energy value of 1804.19 kJ/100g. All essential amino acids are present in C. tripunctatus. Lipids are rich in unsaturated fatty acids, particularly essential fatty acids. In terms of micronutrient composition, the species studied is rich in minerals and vitamins. The mineral content is 10.32% and depends on the nature of the minerals present. Vitamins content also varies. The ratios of minerals, and fatty acids are balanced. These data show the socio-economic importance of dytics consumed in Togo and the quantitative and qualitative richness of C. tripunctatus in nutrients. This species could therefore contribute to the nutritional balance of consumers.
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Larson, Wesley A., James E. Seeb, Carita E. Pascal, William D. Templin, and Lisa W. Seeb. "Single-nucleotide polymorphisms (SNPs) identified through genotyping-by-sequencing improve genetic stock identification of Chinook salmon (Oncorhynchus tshawytscha) from western Alaska." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 5 (May 2014): 698–708. http://dx.doi.org/10.1139/cjfas-2013-0502.
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Genetic stock identification (GSI), an important tool for fisheries management that relies upon the ability to differentiate stocks of interest, can be difficult when populations are closely related. Here we genotyped 11 850 single-nucleotide polymorphisms (SNPs) from existing DNA sequence data available in five closely related populations of Chinook salmon (Oncorhynchus tshawytscha) from western Alaska. We then converted a subset of 96 of these SNPs displaying high differentiation into high-throughput genotyping assays. These 96 SNPs (RAD96) and 191 SNPs developed previously (CTC191) were screened in 28 populations from western Alaska. Regional assignment power was evaluated for five different SNP panels, including a panel containing the 96 SNPs with the highest FST across the CTC191 and RAD96 panels (FST96). Assignment tests indicated that SNPs in the RAD96 were more useful for GSI than those in the CTC191 and that increasing the number of reporting groups in western Alaska from one to three was feasible with the FST96. Our approach represents an efficient way to discover SNPs for GSI and should be applicable to other populations and species.
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White, Helen K., Alexandra E. Morrison, Charvanaa Dhoonmoon, Hasibe Caballero-Gomez, Michelle Luu, Camille Samuels, Charles T. Marx, and Anna P. M. Michel. "Identification of persistent oil residues in Prince William Sound, Alaska using rapid spectroscopic techniques." Marine Pollution Bulletin 161 (December 2020): 111718. http://dx.doi.org/10.1016/j.marpolbul.2020.111718.
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Milosavljević, Aleksandar, Đurađ Milošević, and Bratislav Predić. "SPECIES IDENTIFICATION FOR AQUATIC BIOMONITORING USING DEEP RESIDUAL CNN AND TRANSFER LEARNING." Facta Universitatis, Series: Automatic Control and Robotics 20, no. 1 (April 14, 2021): 001. http://dx.doi.org/10.22190/fuacr201118001m.
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Aquatic insects and other benthic macroinvertebrates are mostly used as bioindicators of the ecological status of freshwaters. However, an expensive and time-consuming process of species identification represents one of the key obstacles for reliable biomonitoring of aquatic ecosystems. In this paper, we proposed a deep learning (DL) based method for species identification that we evaluated on several available public datasets (FIN-Benthic, STONEFLY9, and EPT29) along with our Chironomidae dataset (CHIRO10). The proposed method relies on three DL techniques used to improve robustness when training is done on a relatively small dataset: transfer learning, data augmentation, and feature dropout. We applied transfer learning by employing ResNet-50 deep convolutional neural network (CNN) pretrained on ImageNet 2012 dataset. The results show significant improvement compared to original contributions and confirms that there is a considerable gain when there are multiple images per specimen.
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Scudder, G. G. E. "AQUATIC AND SEMIAQUATIC HEMIPTERA OF PEATLANDS AND MARSHES IN CANADA." Memoirs of the Entomological Society of Canada 119, S140 (1987): 65–98. http://dx.doi.org/10.4039/entm119140065-1.
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AbstractThirteen families containing 138 species of aquatic and semiaquatic Hemiptera have so far been recorded from Canada. The identification of these presents few real difficulties and so the general occurrence of the taxa across the country is fairly well known. Although there has been no intensive study of the Hemipterous insects in peatlands and marshes, the 61 species so far reported from marshes, 32 from fens, and the 33 from bogs appear to be facultative rather than obligatory inhabitants of these habitats. All have been found in other habitats and probably most lentic species occur in marsh habitats. All aquatic and semiaquatic bugs are predators, and most overwinter as adults. Environmental–physiological study of species occurring in bogs has just begun, but evidence suggests that many species have the ability to regulate their internal milieu in water with pH below 4.6–4.7. However, further experiments are needed to determine the physiological limits of tolerance of these insects, the details of osmotic and ionic regulation, and acid–base balance in low-pH water. More collecting is needed in bogs, fens, and marshes, and the life cycle and biology of the Hemiptera occurring in peat-lands still require intensive study.
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Danks, H. V., and David M. Rosenberg. "AQUATIC INSECTS OF PEATLANDS AND MARSHES IN CANADA: SYNTHESIS OF INFORMATION AND IDENTIFICATION OF NEEDS FOR RESEARCH." Memoirs of the Entomological Society of Canada 119, S140 (1987): 163–74. http://dx.doi.org/10.4039/entm119140163-1.
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AbstractAvailable information on the insect fauna of freshwater bogs, fens, and marshes is reviewed. These habitats are extensive and important in Canada. The fauna of marshes is diverse, and appears to consist chiefly of generally distributed lentic species. The fauna of bogs has some specialized elements, but most bog species are generalists. The fauna of Canadian fens is little known, but from limited data for a few groups appears to be moderately rich. Features expected in generalist and specialist species from peatlands and marshes are summarized, and the possible roles of insects in these ecosystems are outlined. Particular needs for future research include the following: careful definition of different kinds of wetland habitats; meticulous sampling of defined habitats to distinguish residents from incidental visitors; and detailed study of the life histories and habits of individual species. Further sampling, and studies of larvae, undoubtedly will increase the numbers of insects known from Canadian peatlands and marshes. About 4000 aquatic insect species are known from Canada. So far only 22% of the species in groups for which detailed information is available have been reported to occur in marshes, and only half as many in peatlands, even though some of the recorded species probably do not breed in all of the habitats from which they have been collected.
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Spigoloni, Zander Augusto, José Vinícius Bernardy, Leandro Schlemmer Brasil, Karina Dias-Silva, Thiago Bernardi Vieira, and Paulo De Marco. "Odonata Concordance amongst aquatic taxa in brazilian savanna streams." International Journal of Odonatology 25 (June 22, 2022): 80–88. http://dx.doi.org/10.48156/1388.2022.1917178.
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Environmental management is one of the most important activities in ecological conservation at present. Faced with various socioeconomic impacts (e.g., urbanization, agriculture, and logging), practical and effective ways to analyze and determine how biodiversity is affected by these anthropogenic activities are essential. Utilizing niche theory helps to understand how similar groups of organisms respond to environmental changes based on the assumption that organisms with some niche overlap (i.e., similar resources) will respond similarly to these changes. Members of the order Odonata are frequently used as biological indicators due to their low survey costs, relatively easy taxonomic identification, and sensibility to environmental changes. In this study, using the PROTEST method, we analyze the cross-taxon congruence between Odonata and two aquatic organisms in Brazilian savanna streams: Gerromorpha and fishes. Although congruence was found between aquatic insects (~ 45%), this result changed when we only considered the species’ genera: no congruence for the aquatic insects was found, but instead we found a congruence between Odonata and fishes (~ 44%). Since Odonata showed congruence with the other groups in different taxonomical resolutions and it is a relatively easy and cheap group to collect and identify, we suggest that Odonata could be used as an indicator of disturbance for this set of organisms and hence serve as an alternative method to traditional environmental management techniques.
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Menabit, Selma, Lavinia Iancu, Ana B. Pavel, Adrian Popa, Naliana Lupascu, and Cristina Purcarea. "Molecular identification and distribution of insect larvae in the Lower Danube River." Oceanological and Hydrobiological Studies 51, no. 1 (March 25, 2022): 74–89. http://dx.doi.org/10.26881/oahs-2022.1.07.
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As a major component of freshwater ecosystems, insect species play an important role in nutrient cycling and are often used as bioindicators of water pollution. Although extensive studies have characterized insects from freshwater habitats, little is known about the distribution of these species along the Lower Sector of the Danube River. Therefore, this survey conducted in the Danube section within the Romanian territory aimed to identify insect larvae belonging to seven different species of Odonata, Trichoptera, Ephemeroptera, Lepidoptera and Megaloptera by DNA barcoding and to investigate their distribution, density and frequency. A total of 41 quantitative macrozoobenthic samples were collected during two consecutive years (2019 and 2020). Species showed large differences in the distribution and density along different sections, and an overall tendency to populate downstream areas, except for Sialis morio. On the other hand, only Hydropsyche bulgaromanorum, Triaenodes bicolor and S. morio larvae were identified in the upstream section (Sulina branch). These data provide baseline information on the larger range of some of the most common aquatic insects in the Romanian Danube section in relation to several environmental parameters based on the first molecular identification of these species using COI gene sequencing.
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Heintz, Ron A., Mark S. Wipfli, and John P. Hudson. "Identification of Marine-Derived Lipids in Juvenile Coho Salmon and Aquatic Insects through Fatty Acid Analysis." Transactions of the American Fisheries Society 139, no. 3 (May 2010): 840–54. http://dx.doi.org/10.1577/t09-115.1.
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Namikoshi, Atsushi, Yasuharu Takashima, Jun Iguchi, Takashi Yanagimoto, and Michiaki Yamashita. "Species identification of Alaska pollock, Gadus spp., and Micromesistius spp. in cod roe products using a PCR-based method." Fisheries Science 77, no. 4 (April 17, 2011): 671–78. http://dx.doi.org/10.1007/s12562-011-0349-4.
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Richardson, Natura, Anne H. Beaudreau, Mark S. Wipfli, and Heather Finkle. "Prey partitioning and use of insects by juvenile sockeye salmon and a potential competitor, threespine stickleback, in Afognak Lake, Alaska." Ecology of Freshwater Fish 26, no. 4 (August 25, 2016): 586–601. http://dx.doi.org/10.1111/eff.12302.
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Taylor, Eric B., Terry D. Beacham, and Masahide Kaeriyama. "Population Structure and Identification of North Pacific Ocean Chum Salmon (Oncorhynchus keta) Revealed by an Analysis of Minisateliite DNA Variation." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 6 (June 1, 1994): 1430–42. http://dx.doi.org/10.1139/f94-143.
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We examined geographic variability in minisatellite DNA in chum salmon (Oncorhynchus keta) from 42 populations from the North Pacific Ocean to (1) determine the extent of regional population structure at minisatellite loci and (2) assess the ability of minisatellite variability to determine the geographic origin in individual chum salmon. Restriction fragments from 1.6 to 13.6 kilobase pairs in molecular weight were resolved with a minisatellite probe. The fragments were inherited from parent to offspring and appeared to represent segregation at two linked loci. Minisateliite DNA variability was negligible between annual samples from the same rivers, and chum salmon fell into three regional population groupings: (i) Japanese, (ii) Russian/Yukon River, and (iii) southeastern Alaska/British Columbia salmon. These regional groupings probably reflect historical patterns of postglacial dispersal of chum salmon from three distinct refugia in the North Pacific. We used restriction fragment counts as input to linear discriminant and neural network classification of independent test samples of salmon. Accuracies of 90–95, 81–86, and 72–80% were achieved when classifying fish as of either Japan/Russia/Yukon River versus southeastern Alaska/British Columbia origin, Japan versus Russia/Yukon River origin, or Russia versus Yukon River origin, respectively.
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Garland, J. A. "IDENTIFICATION OF CHRYSOPIDAE IN CANADA, WITH BIONOMIC NOTES (NEUROPTERA)." Canadian Entomologist 117, no. 6 (June 1985): 737–62. http://dx.doi.org/10.4039/ent117737-6.
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AbstractChrysopidae in Canada comprise 24 species in 9 genera and 2 subfamilies. Additional southern species are mentioned, 1 as a new combination, and other nomenclatorial changes are reviewed in relation to the Canadian fauna. Generic diagnosis of males employs sternum VIII + IX, the arcessus, gonapsis, pseudopenis, and tignum. Generic diagnosis of females is based on the dorsal furrow, ectoprocts, spermatheca, subgenitale, and a non-genitalic trait, the innermost gradate crossvein in the wings. The ecological implications and inherent difficulties in taxonomy are discussed for coloration in Chrysopidae, to develop a practical key to differentiate 26 species using color and other non-genitalic traits. A checklist summarizes maps of the geographic distribution in Canada and notes species in Alaska, based on specimens examined. Patterns of distribution for the Canadian chrysopid fauna are either Holarctic for 1 species or indigenously Nearctic, with eastern, western, or boreal foci. Disjunctions are apparent for species with a more southern, transcontinental distribution, which enter Canada primarily in Ontario and British Columbia. Life-history and bionomic notes are limited to 6 species in Canada, for which synonymies and figures are based on specimens examined. Most data originate from studies performed in Ontario. There are 5 species of parasites from 2 chrysopids. Hosts include 11 species of insects and mites, with 2 cases of hyperpredation. Three insecticides account for the more recent scarcity of chrysopids in the Niagara region. Conclusions relate the following: variable color in the 1 Holarctic species to post-glacial mingling in the northwest; gaps in temporal and spatial distribution to extinctions in progress; and renewed interest in Chrysopidae to earlier research on this group in Canada.
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Pereira, Jardely de Oliveira, Maralina Torres da Silva, Lisandro Juno Soares Vieira, and Rosemara Fugi. "Effects of flood regime on the diet of Triportheus curtus (Garman, 1890) in an Amazonian floodplain lake." Neotropical Ichthyology 9, no. 3 (September 2, 2011): 623–28. http://dx.doi.org/10.1590/s1679-62252011005000029.
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We analyzed the diet of Triportheus curtus in Lake Amapá on the Acre River (AC - Brazil), during three distinct phases of the hydrological cycle (pre-flooding, flooding, and post-flooding stages). The flooding occurred between January and June of 2009. Samples were collected monthly from October 2008 through September 2009. After collection (at 19:00, 01:00, 07:00, and 13:00 hs) and taxonomic identification, fish were eviscerated and their stomachs preserved in a 4% formalin solution for later analysis. The diet was evaluated by the Index of Relative Importance (IRI), and temporal variations (pre-flooding, flooding, and post-flooding) in the diet were summarized by an ordination technique (DCA). The diet of T. curtus was comprised of several orders of insects and microcrustaceans. In the pre-flooding stage, more than 62% of the diet consisted of Ostracoda. In the flooding phase, T. curtus fed mainly on Chaoboridae larvae (Diptera) (44.3%) and terrestrial insects (fragments) (33.7%). In the post-flooding phase, Chaoboridae comprised 80% of the diet. These results indicate that the utilization of food resources by T. curtus was variable, changing with alterations in the availability of resources, as influenced by the hydrological cycle. The population of T. curtus proved to be opportunistic, changing its diet in the course of the hydrological cycle.
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Sturm, Elizabeth A. "Description and Identification of Larval and Juvenile Stenodus leucichthys nelma (Güldenstadt) from Central Alaska." Copeia 1994, no. 2 (May 16, 1994): 472. http://dx.doi.org/10.2307/1446995.
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Dufech, Ana Paula S., Marco A. Azevedo, and Clarice B. Fialho. "Comparative dietary analysis of two populations of Mimagoniates rheocharis (Characidae: Glandulocaudinae) from two streams of Southern Brazil." Neotropical Ichthyology 1, no. 1 (September 2003): 67–74. http://dx.doi.org/10.1590/s1679-62252003000100008.
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The diet of two populations of Mimagoniates rheocharis, from two freshwater streams of the rio Tramandaí, northeastern Rio Grande do Sul, Brazil, are described and compared. The specimens were collected monthly from January 1998 to March 1999, with dip nets and seine nets and preserved in 10% formalin. In laboratory, the standard length of each specimen was measured. The stomachs were removed and dissected for identification of the alimentary items. The data were analyzed using the frequency of occurrence, percent composition and index of alimentary importance methods, being the last two compared among different classes of standard length. Three methods of analysis showed the highest values for allochthonous insects, regardless the locality of collection or body size of the specimens.
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Cronin, Matthew A., William J. Spearman, Richard L. Wilmot, John C. Patton, and John W. Bickham. "Mitochondrial DNA Variation in Chinook (Oncorhynchus tshawytscha) and Chum Salmon (O. keta) Detected by Restriction Enzyme Analysis of Polymerase Chain Reaction (PCR) Products." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 4 (April 1, 1993): 708–15. http://dx.doi.org/10.1139/f93-081.
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We analyzed intraspecific mitochondrial DNA variation in chinook salmon (Oncorhynchus tshawytscha) from drainages in the Yukon River (Alaska and Yukon Territory), the Kenai River (Alaska), and Oregon and California rivers; and chum salmon (O. keta) from the Yukon River and Vancouver Island, and Washington rivers. For each species, three different portions of the mtDNA molecule were amplified separately using the polymerase chain reaction and then digested with at least 19 restriction enzymes. Intraspecific sequence divergences between haplotypes were less than 0.01 base substitution per nucleotide. Nine chum salmon haplotypes were identified. Yukon River chum salmon stocks displayed more haplotypes (eight) than the stocks of Vancouver Island and Washington (two). The most common chum salmon haplotype occurred in all areas. Seven chinook salmon haplotypes were identified. Four haplotypes occurred in the Yukon and Kenai rivers and four occurred in Oregon/California, with only one haplotype shared between the regions. Sample sizes were too small to quantify the degree of stock separation among drainages, but the patterns of variation that we observed suggest utility of the technique in genetic stock identification.
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CHEN, ZHI-TENG. "The little-known larval morphology of two stoneflies of Styloperlidae (Insecta: Plecoptera) in China." Zootaxa 5244, no. 4 (February 21, 2023): 361–76. http://dx.doi.org/10.11646/zootaxa.5244.4.3.
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The stoneflies are a relatively ancient group of aquatic insects. The larvae of stoneflies are exclusively aquatic and are important bioindicators for water quality changes. However, the identification and classification of stonefly larvae are much more difficult than the adults, due to the lack of sufficient descriptions for most stonefly taxa. Styloperlidae is an endemic stonefly family in South Asia. The larval morphology of this family remains less clear in comparison with their adults. In this paper, the larvae of Styloperla inae Chao, 1947 and Cerconychia flectospina Wu, 1962 are described and illustrated based on specimens from China. Their morphology corresponds with the proposed diagnostic larval characters of Styloperlidae in previous studies. Additional auxiliary characters useful for the identification of larvae in Styloperlidae are discussed. The larvae of S. inae and C. flectospina exhibit subtle morphological differences but can be easily distinguished by the presence or absence of dark sclerites on all the thoracic sternal pits.
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Hussein, Hassan, and Beevy S. Suhara. "Diversity assessment of insect species in the Kariavattom campus, University of Kerala." i-manager's Journal on Life Sciences 2, no. 3 (2023): 1. http://dx.doi.org/10.26634/jls.2.3.20768.
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Insects play crucial roles in their specific niches and are vital contributors to various ecosystem processes. They dominate the food webs of both terrestrial and aquatic ecosystems. A study was conducted at Kerala University to evaluate the diversity and abundance of insect species in selected habitats (North and South campus). Sampling was conducted using pitfall traps, sweep nets, beating sheets, Berlese funnels, and hand collection. The collected insects were brought back to the laboratory for identification and counting. A total of 965 insects from 9 Orders and 35 Families were recorded. Indices such as the Shannon index, Simpson index, Margalef index, Evenness index, and Sorenson similarity index were utilized to analyze the diversity of insects. The results indicated that Hymenoptera (30.155%), Orthoptera (25.596%), Lepidoptera (11.192%), and Coleoptera (8.290%) were the most dominant Orders on the campus, comprising 75.233% of the total, whereas the least abundant was Mantodea (0.622%). The South Campus exhibited high species diversity (Margalef index = 8.422), abundance (n = 686), Evenness (E = 0.776), and Shannon diversity (H = 3.124) of insects. It also showed a higher Simpson index (λ = 0.109) compared to the North Campus, which indicated (λ = 0.0610). Moreover, the South Campus recorded a very high number of species, with 56 species (Margalef index = 8.422) compared to 45 species (Margalef index = 7.813) recorded from the North Campus. The higher the index value, the greater the species richness. The high diversity and richness of insects in the southern habitat may be attributed to the large and less disturbed area, the presence of well-distributed ecological niches, more microhabitats, and an abundance of food. Therefore, understanding the factors that influence insect species diversity and abundance at the University of Kerala is important for conservation. This study, thus, highlights the diversity and abundance of insects and the need for sustainable measures to be implemented to conserve these significant species.
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McKinney, Garrett J., Carita E. Pascal, William D. Templin, Sara E. Gilk-Baumer, Tyler H. Dann, Lisa W. Seeb, and James E. Seeb. "Dense SNP panels resolve closely related Chinook salmon populations." Canadian Journal of Fisheries and Aquatic Sciences 77, no. 3 (March 2020): 451–61. http://dx.doi.org/10.1139/cjfas-2019-0067.
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Chinook salmon (Oncorhynchus tshawytscha) are migratory fish that are highly valued for subsistence, sport, and commercial fisheries throughout their native range. Populations of Chinook salmon in western Alaska have exhibited long-term declines, leading to restrictions on harvests. Management priorities require greater resolution for genetic stock identification (GSI) than is available with current methods. We leveraged RADseq, TaqMan, and GT-seq data originating from multiple sources, collected through time, to develop a set of GT-seq panels containing 1092 single nucleotide polymorphisms (SNPs) that improved GSI resolution in western Alaska for at-sea and in-river sampling. We generated a dense linkage map to ensure that markers selected for panels spanned the entire genome. In addition, we identified multiple RADseq markers that were associated with sex; these aligned to a 5-centimorgan (cM) region on the sex chromosome. Finally, we developed a bioinformatic pipeline to streamline analysis of GT-seq data that is capable of genotyping microhaplotypes and paralogs, both of which can improve GSI resolution over traditional single-SNP data. Our panels and pipeline provide tools for management agencies to rapidly and easily analyze large-scale genotyping projects.
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Bigler, Brian. "Mechanism and Occurrence of Focal Scale Resorption among Chum Salmon (Oncorhynchus keta) of the North Pacific Ocean." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 7 (July 1, 1989): 1147–53. http://dx.doi.org/10.1139/f89-149.
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A recently documented scale characteristic of chum salmon (Oncorhynchus keta) originating from Hokkaido, Japan, has been found distributed almost exclusively among stocks of Asian origin. Scales from 10 544 chum salmon collected from 25 near-shore locations throughout the North Pacific Ocean were examined. Resorption of the scale focus, including instances where an easily visible hole had been formed, was found among 10.8% of Japanese chum salmon and 15.9% of chum salmon originating from the Soviet Union. In North America, this trait was infrequent (< 0.5%) among populations north of the Aleutian Islands, British Columbia, and Puget Sound, and was not found in Cook Inlet, Prince William Sound, and Southeast Alaska. Focal scale resorption arises from osteoclastic cellular activity, most likely following the first winter of life, and remains as a permanent mark thereafter. This unique, uniformly occurring, easily identifiable scale characteristic will provide a valuable tool for stock identification. Evidence of focal scale resorption is also reported in sockeye (O. nerka), coho (O. kisutch), and king salmon (O. tshawytscha), but was not found in pink salmon (O. gorbuscha), sampled from locations in Alaska.
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Wang, Ju Hyoun, Hee-kyu Choi, Hyuk Je Lee, and Hwang Goo Lee. "On the Species Identification of Two Non-Native Tilapia Species, Including the First Record of a Feral Population of Oreochromis aureus (Steindachner, 1864) in South Korea." Animals 13, no. 8 (April 14, 2023): 1351. http://dx.doi.org/10.3390/ani13081351.
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Tilapia is an invasive species that has become widely distributed around the world. In Korea, introduced tilapia into its aquatic ecosystem for the first time with a species from Thailand in 1955, and later additionally introduced two more species from Japan and Taiwan, thus securing a total of three species of tilapia (O. niloticus, O. mossambicus and O. aureus) as food resources. Since then, O. niloticus has been reported to inhabit certain streams with thermal effluent outlets. Morphological species identification is very difficult for tilapia and a combined analysis of morphological and molecular-based species identification is therefore necessary. This study investigated a tilapia population that inhabits a thermal effluent stream (Dalseo Stream) in Daegu Metropolitan City, Korea, in order to conduct a morphological and genetic species identification of this population. In total, 37 tilapia individuals were sampled. The results of the morphological and genetic species identification analyses found that two species, O. aureus and O. niloticus, inhabit the Dalseo Stream. In Korea, the habitat of the O. niloticus natural population has been reported, but the O. aureus natural population has not been reported. Thus, we observed for the first time that a new invasive species, O. aureus, inhabits a stream in Korea. They are known to cause disturbances to aquatic organisms (e.g., fish, aquatic insects, plankton, aquatic plants) and the habitat environment (e.g., water quality, bottom structure). Accordingly, it is important to study the ecological effects of O. aureus and O. niloticus on the corresponding freshwater ecosystem closely and to prepare a management plan to prevent the spread of these species, as they are notoriously invasive.
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Meyers, TR, J. Sullivan, E. Emmenegger, J. Follett, S. Short, WN Batts, and JR Winton. "Identification of viral hemorrhagic septicemia virus isolated from Pacific cod Gadus macrocephalus in Prince William Sound, Alaska, USA." Diseases of Aquatic Organisms 12 (1992): 167–75. http://dx.doi.org/10.3354/dao012167.
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Jorgensen, Elaina M. "Identification, distribution and relative abundance of paralarval gonatid squids (Cephalopoda: Oegopsida: Gonatidae) from the Gulf of Alaska, 2001–2003." Journal of Molluscan Studies 73, no. 2 (May 1, 2007): 155–65. http://dx.doi.org/10.1093/mollus/eym010.
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Wood, C. C., S. McKinnell, T. J. Mulligan, and D. A. Fournier. "Stock Identification with the Maximum-Likelihood Mixture Model: Sensitivity Analysis and Application to Complex Problems." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 4 (April 1, 1987): 866–81. http://dx.doi.org/10.1139/f87-105.
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Simulations were performed to evaluate the bias and precision of stock composition estimates from the maximum-likelihood mixture model using hypothetical multilocus characters. Bias and precision were examined in relation to the number of stocks being resolved, the number of loci available, and the difference in allelic frequency among stocks at each locus, using Monte Carlo simulations with different levels of sampling error in the mixture and learning samples. Model performance improved with increasing stock separation and number of loci available. Bias was not affected by the number of stocks resolved in simulations where mixture contributions from individual stocks remained constant. These results provide guidelines for reducing the complexity of genetic stock-identification problems by summing estimated mixing proportions for individual stocks within groupings based on stock similarity. The trade-off between improved accuracy and level of grouping can be examined graphically to determine the most useful level of grouping for the problem at hand. We illustrate this procedure with a real example from mixed-stock fisheries on sockeye salmon (Oncorhynchus nerka) along the British Columbia – Alaska coast.
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McKinney, Garrett J., James E. Seeb, and Lisa W. Seeb. "Managing mixed-stock fisheries: genotyping multi-SNP haplotypes increases power for genetic stock identification." Canadian Journal of Fisheries and Aquatic Sciences 74, no. 4 (April 2017): 429–34. http://dx.doi.org/10.1139/cjfas-2016-0443.
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A common challenge for fisheries management is resolving the relative contribution of closely related populations where accuracy of genetic assignment may be limited. An overlooked method for increasing assignment accuracy is the use of multi-SNP (single nucleotide polymorphism) haplotypes rather than single-SNP genotypes. Haplotypes increase power for detecting population structure, and loci derived from next-generation sequencing methods often contain multiple SNPs. We evaluated the utility of multi-SNP haplotyping for mixture analysis in western Alaska Chinook salmon (Oncorhynchus tshawytscha). Multi-SNP haplotype data increased the accuracy of mixture analysis for closely related populations by up to seven percentage points relative to single-SNP genotype data for a set of 500 loci; 90% accuracy was achievable with as few as 150 loci with multi-SNP haplotypes but required at least 300 loci with single-SNP genotypes. Individual assignment to reporting groups showed an even greater increase in accuracy of up to 17 percentage points when multi-SNP haplotypes were used. Haplotyping multiple SNPs shows promise to improve the accuracy of assigning unknown fish to population of origin whenever haplotype data are available.
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Spies, I. B., S. Gaichas, D. E. Stevenson, J. W. Orr, and M. F. Canino. "DNA-based identification of Alaska skates (Amblyraja, Bathyraja and Raja: Rajidae) using cytochrome c oxidase subunit I (coI) variation." Journal of Fish Biology 69, sb (December 2006): 283–92. http://dx.doi.org/10.1111/j.1095-8649.2006.01286.x.
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Arostegui, M. C., and T. P. Quinn. "Trophic ecology of nonanadromous rainbow trout in a post-glacial lake system: partial convergence of adfluvial and fluvial forms." Canadian Journal of Zoology 96, no. 8 (August 2018): 818–27. http://dx.doi.org/10.1139/cjz-2017-0201.
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The rainbow trout (Oncorhynchus mykiss (Walbaum, 1792)) is one of many salmonid species exhibiting a gradient of life histories including fluvial (stream-resident), anadromous (ocean-migrant), and adfluvial (lake-migrant) forms, the last of which is less extensively studied than the other two. Our goal was to determine the extent of diet segregation between fluvial and adfluvial rainbow trout. We collected stomach content and stable isotope data on rainbow trout sampled in stream and lake habitats in a southwestern Alaska watershed during summer and compared them with data on sympatric stream- and lake-specialist char species, Dolly Varden (Salvelinus malma (Walbaum in Artedi, 1792)) and Arctic char (Salvelinus alpinus (Linnaeus, 1758)), respectively. Rainbow trout in streams fed largely on aquatic insects, while those in the lake ate primarily benthic snails and amphipods. The trophic segregation of stream-resident and lake-migrant rainbow trout mirrored but was less extreme than the divergence of lotic Dolly Varden and lentic Arctic char in the same system. Spawning sockeye salmon (Oncorhynchus nerka (Walbaum in Artedi, 1792)) provided a nutrient subsidy in the form of eggs that supported rainbow trout in both stream and lake (littoral) habitats, causing their isotopic signatures to converge. This study augments knowledge of partial migration and trophic divergence within populations.
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Gavrilov-Zimin, I. A., and A. S. Kurochkin. "Millennial zoological mystery of medieval Persian scientists." Zoosystematica Rossica 28, no. 2 (August 20, 2019): 201–27. http://dx.doi.org/10.31610/zsr/2019.28.2.201.
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Great medieval scientist-polymath Abu Rayhan Al-Beruni (973–1050) wrote in his book “Pharmacognosy” about some kind of “worms” inhabiting willows in Azerbaijan and Southern Iran and used by native people for producing of a red dye. It was unclear during one thousand years which organisms Al-Beruni noted as those dye-producing “worms”. Some modern authors even suggested that the relevant medieval text was partly erroneous. To the contrary, in the present paper we, for the first time, consider some species of the felt scale insects (Coccinea: Eriococcidae) as the organisms, which have probably been used for the production of the red dye in the medieval countries of Western and Central Asia. These insects are several species from two closely related genera Acanthococcus Signoret, 1875 and Gossyparia Signoret, 1875. The review of biological characters, identification key, new figures and colour photographs are provided for the species of Acanthococcus and Gossyparia associated with Salix spp. in the Asiatic Region. Acanthococcus turanicus Matesova, 1967, syn. nov. is placed in synonymy with A. salicis (Borchsenius, 1938), and A. altaicus Matesova, 1967, syn. nov. is placed in synonymy with A. spiraeae Borchsenius, 1949. Earlier discovered synonymy of A. melnikensis (Hodgson et Trencheva, 2008) with A. aceris Signoret, 1875 is discussed. Some other dye-producing scale insects and their pigments are also briefly considered.
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Wood, Chris C., Dennis T. Rutherford, and Skip McKinnell. "Identification of Sockeye Salmon (Oncorhynehus nerka) Stocks in Mixed-stock Fisheries in British Columbia and Southeast Alaska using Biological Markers." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 12 (December 1, 1989): 2108–20. http://dx.doi.org/10.1139/f89-261.
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We demonstrate the present analytical capability and the potential for coast-wide stock identification of sockeye salmon (Oncorhynchus nerka) using reference sampling data from 51 principal stocks in British Columbia and Southeast Alaska situated between the Fraser and Taku Rivers. We evaluate the relative accuracy and precision of stock composition estimates from maximum likelihood mixture analysis with four types of biological markers, either alone or in combination; these include freshwater age, six scale pattern variables, the prevalence of the brain parasite Myxobolus neurobius, and five biochemical genetic (electrophoretic) traits. Using all markers in combination, estimates of mixing proportions for all test mixtures are acceptable for most purposes (roughly ± 10% with 95% confidence) providing all samples are representative and mixture samples are large ([Formula: see text] fish). The reliability of these estimates is greatly reduced when reference samples are corrupted to simulate observed annual variation in scale pattern markers. Annual variation may preclude the use of scale pattern markers for complicated stock identification problems where representative reference samples cannot be obtained annually, or until after the fishing period. In contrast, no significant annual variation is detectable for biochemical genetic and brain parasite markers in stocks that have been sampled repeatedly. Using only these stable markers, contributions from about 15 different groups of the 51 stocks can be estimated with acceptable precision, but in general, estimates for individual stocks are unreliable.
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Yan, Chuncai, Xiaoya Sun, Wei Cao, Ruoqun Li, Cong Zhao, Zeyang Sun, Wenbin Liu, and Lina Pan. "Identification and expression pattern of chemosensory genes in the transcriptome of Propsilocerus akamusi." PeerJ 8 (July 21, 2020): e9584. http://dx.doi.org/10.7717/peerj.9584.
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Chironomidae is the most ecologically diverse insects in aquatic and semi-aquatic habitats. Propsilocerus akamusi (Tokunaga) is a dominant and ubiquitous chironomid species in Eastern Asia and its morphologically unique larvae are also considered as indicator organisms to detect water contamination, potential toxicity and waterborne pathogens. Since few studies to date have focused on the olfactory system of P. akamusi, our study aims to elucidate the potential functions of chemosensory genes in P. akamusi. In our study, we found that although signals released from male groups might attract female swarmers, it was a completely male-dominated mating process. Sequencing the transcriptome of P. akamusi on an Illumina HiSeq platform generated 4.42, 4.46 and 4.53 Gb of clean reads for heads, legs, and antennae, respectively. 27,609 unigenes, 20,379 coding sequences (CDSs), and 8,073 simple sequence repeats were finally obtained. The gene-level differential expression analysis demonstrated variants among three different tissues, including 2,019 genes specifically expressed in heads, 1,540 genes in legs, and 2,071 genes in antennae. Additionally, we identified an assortment of putative olfactory genes consisting of 34 odorant binding proteins, 17 odorant receptors, 32 gustatory receptors, 22 ionotropic receptors, six chemosensory proteins as well as 3 sensory neuron membrane proteins; their relative abundances in the above three tissues were also determined by RT-qPCR. Our finding could allow a more plausible understanding of certain olfaction-mediated behaviors in groups of this macroinvertebrate.
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Craig, P. C. "Identification of Sockeye Salmon (Oncorhynchus nerka) Stocks in the Stikine River Based on Egg Size Measurements." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 11 (November 1, 1985): 1696–701. http://dx.doi.org/10.1139/f85-212.
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The Stikine River in southeastern Alaska supports two principal stocks of sockeye salmon (Oncorhynchus nerka). An expedient means of separating these stocks when they enter freshwater is by egg size and egg mass measurements. Eggs of sockeye that spawn in the Tahltan Lake system are smaller than sockeye spawning elsewhere in the Stikine drainage, a difference supported by an independent stock identification method (scale pattern analysis). Tahltan females have only slightly developed ovaries (1–3% of body weight) and small eggs (2.0–3.5 mm) when they enter freshwater; they enter the river earlier (2–3 wk) and travel farther upstream to spawn than non-Tahltan sockeye. The latter group has more developed ovaries (5–16% of body weight) and larger eggs (3.5–6.2 mm) when they enter the river. Thus, an assessment of egg sizes of sockeye caught in the river can provide on-site information about stock composition and run timing. These data and escapement counts at Tahltan Lake indicate that the total escapement to the Stikine in 1983 was 61 000 to 71 000 sockeye of which 45–53% were Tahltan stock and 47–55% spawned eleswhere in the drainage.
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Li, Lijuan, Xuwang Yin, Qianruo Wan, Dilina Rusitanmu, and Jie Han. "Diet Diversity of the Fluviatile Masu Salmon, Oncorhynchus masou (Brevoort 1856) Revealed via Gastrointestinal Environmental DNA Metabarcoding and Morphological Identification of Contents." Biology 13, no. 2 (February 18, 2024): 129. http://dx.doi.org/10.3390/biology13020129.
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Masu salmon, Oncorhynchus masou (Brevoort 1856), a commercially important fish species endemic to the North Pacific Ocean, attained national second-level protected animal status in China in 2021. Despite this recognition, knowledge about the trophic ecology of this fish remains limited. This study investigated the diet diversity of fluviatile Masu salmon in the Mijiang River, China, utilizing the gastrointestinal tract environmental DNA (GITeDNA) metabarcoding and morphological identification. The results revealed a diverse prey composition, ranging from terrestrial and aquatic invertebrates to small fishes. The fluviatile Masu salmon in general consumed noteworthily more aquatic prey than terrestrial prey. There were much more prey taxa and a higher diet diversity detected by GITeDNA metabarcoding than by morphological identification. GITeDNA metabarcoding showed that larger and older Masu salmon consumed significantly more terrestrial insects than aquatic prey species did, with 7366 verses 5012 sequences in the group of ≥20 cm, 9098 verses 4743 sequences in the group of ≥100 g and 11,540 verses 729 sequences in the group of age 3+. GITeDNA metabarcoding also showed size- and age-related diet diversity, indicating that the dietary niche breadth and trophic diversity of larger and older Masu salmon increased with food resources expanding to more terrestrial prey. Terrestrial invertebrates of riparian habitats play a vital role in the diet of fluviatile Masu salmon, especially larger individuals, highlighting their importance in connecting aquatic and terrestrial food webs. Conservation plans should prioritize the protection and restoration of riparian habitats. This study advocates the combined use of GITeDNA metabarcoding and morphological observation for a comprehensive understanding of fish diet diversity.
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Hamilton, Veronica A., Sylvia S. Lee, Allison R. Rober, Paula C. Furey, Kalina M. Manoylov, and Kevin H. Wyatt. "A Voucher Flora of Diatoms from Fens in the Tanana River Floodplain, Alaska." Water 15, no. 15 (August 2, 2023): 2803. http://dx.doi.org/10.3390/w15152803.
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Climate change and human activities may alter the structure and function of boreal peatlands by warming waters and changing their hydrology. Diatoms can be used to assess or track these changes. However, effective biomonitoring requires consistent, reliable identification. To address this need, this study developed a diatom voucher flora of species found across a boreal fen gradient (e.g., vegetation) in interior Alaskan peatlands. Composite diatom samples were collected bi-weekly from three peatland complexes over the 2017 summer. The morphological range of each taxon was imaged. The fens contained 184 taxa across 38 genera. Eunotia (45), Gomphonema (23), and Pinnularia (20) commonly occurred in each peatland. Tabellaria was common in the rich and moderate fen but sparse in the poor fen. Eunotia showed the opposite trend. Approximately 11% of species are potentially novel and 25% percent matched those at risk or declining in status on the diatom Red List (developed in Germany), highlighting the conservation value of boreal wetlands. This voucher flora expands knowledge of regional diatom biodiversity and provides updated, verifiable taxonomic information for inland Alaskan diatoms, building on Foged’s 1981 treatment. This flora strengthens the potential to effectively track changes in boreal waterways sensitive to climate change and anthropogenic stressors.
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Labay, V. S. "Additional data on morphology and distribution of Melitoides valida (Shoemaker, 1955) (Amphipoda, Melitidae)." Marine Biological Journal 6, no. 1 (March 23, 2021): 58–66. http://dx.doi.org/10.21072/mbj.2021.06.1.05.
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The genus Melitoides Gurjanova, 1934 (Amphipoda, Melitidae) includes three species from the Arctic and northwestern Pacific: Melitoides makarovi Gurjanova, 1934, M. valida (Shoemaker, 1955), and M. kawaii Labay, 2014. M. makarovi and M. kawaii only were recorded until recently in the seas of the Russian Far East. Only two specimens of M. valida were found once near the Arctic coast of Alaska; therefore, the morphological description of the species was incomplete, which led to difficulties with its generic identification. For the first time, M. valida was found in the seas of the Russian Far East in September 2018 on the shelf of the Sea of Okhotsk, near the North-Eastern Sakhalin Island at the depth of 29 m on the sand bottom. Detailed re-description of the species was carried out using optical and electronic scanning microscopes by the Coleman protocol. The material collected is stored at the Crustacea collection of the Zoological Museum of Far Eastern Federal University (Vladivostok). The specimen from the Sea of Okhotsk is identical to the specimens of the type series from the Arctic coast of Alaska in the form of dorsal carination (with several teeth on posterior margin of pleon segments 2, 3 and urosomites 1, 2), in the structure of pereopods 1–7, especially in the form of propodus of pereopods 2 (palm with distinct posterior-distal tooth, as well as with three large and one small obtuse palmar teeth). M. valida description has been substantially supplemented, and information on its range has been expanded.
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SALMELA, JUKKA, OSKARI HÄRMÄ, and DEREK J. TAYLOR. "Chaoborus flavicans Meigen (Diptera, Chaoboridae) is a complex of lake and pond dwelling species: a revision." Zootaxa 4927, no. 2 (February 12, 2021): 151–96. http://dx.doi.org/10.11646/zootaxa.4927.2.1.
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Chaoborus flavicans (Meigen) is a widespread and much studied lacustrine phantom midge. As larvae, these insects are important aquatic predators. Based on the available type material, morphology of immature stages and adults, their aquatic habitat, and DNA barcodes, C. flavicans is shown to be a composite of at least four species, with three of these named here. Chaoborus flavicans is primarily a lake-dwelling species with a Holarctic range. Chaoborus albipes (Johannsen, 1903 stat. rev.) and C. posio Salmela sp. n. are pond-dwelling Holarctic and north European species, respectively. The position of the larval subordinate mandibular tooth at the vertex of the second and fourth teeth is a synapomorphy of the Chaoborus flavicans species complex. We present an identification key to fourth instar larvae, pupae, and adult males. We also designate the lectotype and paralectotypes of Sayomyia rotundifolia Felt, 1904 (syn. nov. of C. albipes). We hypothesize that a fourth species of the species complex is present in Japan. Our revision indicates that Holarctic shallow ponds contain a hidden diversity of predators (C. albipes and C. posio sp. n.).
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Urbán R., J., A. Jaramillo L., A. Aguayo L., P. Ladrón de Guevara P., M. Salinas Z., C. Alvarez F., L. Medrano G., et al. "Migratory destinations of humpback whales wintering in the Mexican Pacific." J. Cetacean Res. Manage. 2, no. 2 (September 1, 2000): 101–10. http://dx.doi.org/10.47536/jcrm.v2i2.493.
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The migratory destinations of humpback whales that winter off the Pacific coast of Mexico were examined using photo-identification. Fluke photographs taken between 1983 and 1993 from the three main whale aggregations in this area (383 from the Mainland coast; 471 from Baja California Peninsula; and 450 from Revillagigedo Archipelago) were compared with collections from all known summering grounds in the North Pacific (593 off California-Oregon-Washington; 48 off British Columbia; 429 off Southeastern Alaska; 141 off Prince William Sound; and 133 from the western Gulf of Alaska ). The migratory movements of these whales were clearly non-random. The results of the photographic comparisons and the statistical tests show clear evidence for preferred migratory destinations of humpback whales from Mainland and Baja California to California-Oregon-Washington and British Columbia summering regions. Nevertheless, differences in whale abundance estimates between these summering and wintering aggregations indicate the presence of some unsampled summering region(s). The principal migratory destination was not detected for the Revillagigedo region, although matches were found with all the summering regions sampled. This supports the hypothesis that the humpback whales from Revillagigedo are separate from the ‘American stock’. Based on the known abundance estimates, historical whaling records and genetic structure of the populations, it is proposed that historical feeding grounds off the Aleutian Islands and/or the Bering Sea are the main summer destinations of the whales from Revillagigedo.
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TRUMAN, JAMES W., and PHILIP F. COPENHAVER. "The Larval Eclosion Hormone Neurones in Manduca Sexta: Identification of the Brain-Proctodeal Neurosecretory System." Journal of Experimental Biology 147, no. 1 (November 1, 1989): 457–70. http://dx.doi.org/10.1242/jeb.147.1.457.
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Larval and pupal ecdyses of the moth Manduca sexta are triggered by eclosion hormone (EH) released from the ventral nervous system. The major store of EH activity in the latter resides in the proctodeal nerves that extend along the larval hindgut. At pupal ecdysis, the proctodeal nerves show a 90% depletion of stored activity, suggesting that they are the major release site for the circulating EH that causes ecdysis. Surgical experiments involving the transection of the nerve cord or removal of parts of the brain showed that the proctodeal nerve activity originates from the brain. Retrograde and anterograde cobalt fills and immunocytochemistry using antibodies against EH revealed two pairs of neurons that reside in the ventromedial region of the brain and whose axons travel ipsilaterally along the length of the central nervous system (CNS) and project into the proctodeal nerve, where they show varicose release sites. These neurons constitute a novel neuroendocrine pathway in insects which appears to be dedicated solely to the release of EH.
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Gasper, Jason R., and Gordon H. Kruse. "Modeling of the spatial distribution of Pacific spiny dogfish (Squalus suckleyi) in the Gulf of Alaska using generalized additive and generalized linear models." Canadian Journal of Fisheries and Aquatic Sciences 70, no. 9 (September 2013): 1372–85. http://dx.doi.org/10.1139/cjfas-2012-0535.
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The Pacific spiny dogfish (Squalus suckleyi) is a common bycatch species in the Gulf of Alaska. Their spatial distribution is poorly understood, as most catch is discarded at sea. We analyzed spiny dogfish spatial distribution from fishery-dependent and -independent observations of longline gear between 1996 and 2008 using generalized additive and generalized linear models. Poisson, negative binomial, and quasi-Poisson error structures were investigated; the quasi-Poisson generalized additive model fit best. Models showed that spiny dogfish catches were concentrated east of Kodiak Island in waters ≤100 m deep. Results facilitate design of future spiny dogfish assessment surveys and identification of areas in which to focus at-sea observations for fishing mortality estimation, and provide the basis for first-ever designation of spiny dogfish essential fish habitat, despite US legal requirements for essential fish habitat designations since 1996. Identified areas of high bycatch may expedite spatial management by indicating areas in which directed spiny dogfish fisheries could be focused or, conversely, areas in which heightened conservation and catch accounting efforts would be most effective to prevent overfishing of this long-lived, late-maturing species.
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Beacham, Terry D., John R. Candy, Brenda McIntosh, Cathy MacConnachie, Amy Tabata, Kristina M. Miller, and Ruth E. Withler. "DNA-Level Variation of Sockeye Salmon in Southeast Alaska and the Nass and Skeena Rivers, British Columbia, with Applications to Stock Identification." North American Journal of Fisheries Management 25, no. 3 (August 2005): 763–76. http://dx.doi.org/10.1577/m04-080.1.
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Ruggerone, Gregory T., and Brendan M. Connors. "Productivity and life history of sockeye salmon in relation to competition with pink and sockeye salmon in the North Pacific Ocean." Canadian Journal of Fisheries and Aquatic Sciences 72, no. 6 (June 2015): 818–33. http://dx.doi.org/10.1139/cjfas-2014-0134.
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Sockeye salmon (Oncorhynchus nerka) populations from Southeast Alaska through British Columbia to Washington State have experienced similar declines in productivity over the past two decades, leading to economic and ecosystem concerns. Because the declines have spanned a wide geographic area, the primary mechanisms driving them likely operate at a large, multiregional scale at sea. However, identification of such mechanisms has remained elusive. Using hierarchical models of stock–recruitment dynamics, we tested the hypothesis that competition between pink (Oncorhynchus gorbuscha) and sockeye salmon for prey has led to reduced growth and productivity and delayed maturation of up to 36 sockeye populations spanning the region during the past 55 years. Our findings indicate the abundance of North Pacific pink salmon in the second year of sockeye life at sea is a key factor contributing to the decline of sockeye salmon productivity, including sockeye in the Fraser River where an increase from 200 to 400 million pink salmon is predicted to reduce sockeye recruitment by 39%. Additionally, length-at-age of Fraser River sockeye salmon declined with greater sockeye and pink salmon abundance, and age at maturity increased with greater pink salmon abundance. Our analyses provide evidence that interspecific competition for prey can affect growth, age, and survival of sockeye salmon at sea.
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Cunningham, Curry J., Trevor A. Branch, Tyler H. Dann, Matt Smith, James E. Seeb, Lisa W. Seeb, and Ray Hilborn. "A general model for salmon run reconstruction that accounts for interception and differences in availability to harvest." Canadian Journal of Fisheries and Aquatic Sciences 75, no. 3 (March 2018): 439–51. http://dx.doi.org/10.1139/cjfas-2016-0360.
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Understanding population-specific spawner–recruit relationships is necessary for sustainable salmon management. Where multiple populations are harvested together, run reconstruction methods partition mixed-stock catches and allocate recruits back to their populations of origin. Traditional run reconstruction methods often use age composition data to inform catch partitioning. However age-only methods do not account for stock-specific differences in the availability of fish to harvest within fishing areas or the incidental harvest of nontarget stocks in nearby fishing areas. Advances in molecular genetic techniques permit genetic stock identification (GSI) of both contemporary and historical catch samples. We present a statistical model for salmon run reconstruction that utilizes both age composition and GSI data to estimate differences in the availability of stocks within, and interception rates among, terminal fisheries. When applied to the commercial sockeye salmon (Oncorhynchus nerka) fishery in Bristol Bay, Alaska, new estimates of population productivity differed from those generated using previous age-only methods by 0.1%–155.1%, with stock-specific mean absolute percent differences of 9.7%–38.7% across years, underscoring the value of genetic data for run reconstruction. With more accurate run reconstruction methods, spawner–recruit relationships can be identified more precisely, thus providing more accurate management targets for salmon fisheries.
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JUDSON, SARAH W., and C. RILEY NELSON. "A Guide to Mongolian Stoneflies (Insecta: Plecoptera)." Zootaxa 3541, no. 1 (November 6, 2012): 1. http://dx.doi.org/10.11646/zootaxa.3541.1.1.
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Since the early 1900s, efforts have been made to catalogue the stoneflies of Mongolia. Taxonomic work from 1960 to1980 greatly expanded basic lists of stoneflies in Mongolia, but no comprehensive survey or synthesis of this dispersedliterature has been completed. In conjunction with a modern survey of the aquatic insects of Mongolia, we collectedPlecoptera on a series of expeditions to the Selenge (north) and Altai (west) regions of Mongolia. A total of 48 speciesdistributed in 24 genera and 8 families were documented, including 3 of the 5 Mongolian endemics, 2 new species re-cords for Mongolia, and 1 species new to science. The majority of the fauna is representative of the East Palearcticregion. The 800+ specimen records were used to validate historical species lists, document species ranges with georef-erenced localities, and create identification tools to be used by Mongolian and international researchers with a broadrange of taxonomic expertise. These identification tools include a generic-level key to nymphs, species diagnoses, aswell as known species range and predicted species range maps created using Ecological Niche Modeling. These toolsare primarily intended for use by Mongolian scientists, sampling teams, and community water quality monitoringgroups, as well as general use by researchers interested in biogeography, ecology, and water quality applications ofMongolian Plecoptera. With this work, we hope to equip Mongolians with the scientific resources to protect their valuable and vulnerable water resources.
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Miaud, Claude, Véronique Arnal, Marie Poulain, Alice Valentini, and Tony Dejean. "eDNA Increases the Detectability of Ranavirus Infection in an Alpine Amphibian Population." Viruses 11, no. 6 (June 6, 2019): 526. http://dx.doi.org/10.3390/v11060526.
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The early detection and identification of pathogenic microorganisms is essential in order to deploy appropriate mitigation measures. Viruses in the Iridoviridae family, such as those in the Ranavirus genus, can infect amphibian species without resulting in mortality or clinical signs, and they can also infect other hosts than amphibian species. Diagnostic techniques allowing the detection of the pathogen outside the period of host die-off would thus be of particular use. In this study, we tested a method using environmental DNA (eDNA) on a population of common frogs (Rana temporaria) known to be affected by a Ranavirus in the southern Alps in France. In six sampling sessions between June and September (the species’ activity period), we collected tissue samples from dead and live frogs (adults and tadpoles), as well as insects (aquatic and terrestrial), sediment, and water. At the beginning of the breeding season in June, one adult was found dead; at the end of July, a mass mortality of tadpoles was observed. The viral DNA was detected in both adults and tadpoles (dead or alive) and in water samples, but it was not detected in insects or sediment. In live frog specimens, the virus was detected from June to September and in water samples from August to September. Dead tadpoles that tested positive for Ranavirus were observed only on one date (at the end of July). Our results indicate that eDNA can be an effective alternative to tissue/specimen sampling and can detect Ranavirus presence outside die-offs. Another advantage is that the collection of water samples can be performed by most field technicians. This study confirms that the use of eDNA can increase the performance and accuracy of wildlife health status monitoring and thus contribute to more effective surveillance programs.
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Halmi, Mohd Izuan Effendi, Wan Lutfi Wan Johari, Mohd Shukuri Mohd Ali, and Noor Azmi Shaharuddin. "Isolation of molybdenum-reducing bacterium; <i>Serratia</i> sp. strain MIE2 from agriculture soil and its potential use in soil bioremediation." Journal of Biochemistry, Microbiology and Biotechnology 5, no. 2 (December 31, 2017): 12–18. http://dx.doi.org/10.54987/jobimb.v5i2.342.
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Molybdenum is reported to be very toxic to ruminants and shows evidence of spermatogenesistoxicity in animals and insects. Hence, its removal is important. In this study, we report on thefirst isolation of molybdenum-reducing bacterium from agricultural soil. The bacterium reduceshexavalent molybdenum (sodium molybdate) to molybdenum blue (Mo-blue); a colloidalproduct, which can be trapped and removed from solution. Phylogenetic analysis resulted in atentative identification of the bacterium as Serratia sp. strain MIE2. The optimum conditions forMo-blue production using the normal one-variable-at-a-time (OVAT) approach were 10 mM ofsodium molybdate, pH 6.0, a temperature of 35°C, ammonium sulphate at 10 g/L as the nitrogensource and sucrose concentrations of between 30-50 g/L as the carbon source and electron donorfor molybdate. Studies on the effects of pesticides and solvents on Mo-blue production showedthat Mo-blue production from whole cells was relatively more affected by these xenobioticscompared to the crude enzyme. Nevertheless, the strain was resistant to most of the xenobioticstested. Based on the strain MIE characteristics, the bacterium will be a suitable candidate for theremediation of aquatic bodies and agricultural soils contaminated with molybdenum.
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Koski, W. R., J. Zeh, J. Mocklin, A. R. Davis, D. J. Rugh, J. C. George, and R. Suydam. "Abundance of Bering-Chukchi-Beaufort bowhead whales (Balaena mysticetus) in 2004 estimated from photo-identification data." J. Cetacean Res. Manage. 11, no. 2 (February 14, 2023): 89–99. http://dx.doi.org/10.47536/jcrm.v11i2.615.
Full textAbstract:
Ice-based surveys near Point Barrow, Alaska, have been used to obtain most estimates of abundance for the Bering-Chukchi-Beaufort (B-C-B) stock of bowhead whales, but global warming has raised concerns that ice-based surveys may not be practical in the future. Aerial photographic surveys provide an alternative method for obtaining abundance estimates and may replace ice-based surveys. Aerial photographic surveys were conducted near Point Barrow during the spring migrations of bowhead whales in 2003 and 2004 and, in 2005, in the northern Bering Sea in spring and near Barrow in fall. The 2003 survey was the most complete photographic survey of the population conducted to date. These surveys provided photo-identification data for use in capture-recapture analyses. A screening procedure was used to define which whales captured in 2003, 2004 and/or 2005 were marked and could be reidentified if photographed on another occasion. An estimate of the number of marked whales was obtained using a closed population model for capture-recapture data. Several models were investigated, including models that accounted for heterogeneity in capture probabilities, but a simple model with no covariates produced the most precise estimate. To account for unmarked whales, the estimate of marked whales was divided by an estimate of the proportion of the bowhead population that was marked based on the 1989–2004 spring photographic surveys near Point Barrow. Abundance of the B-C-B bowhead population in 2004 (excluding calves) was estimated to be 12,631 with CV 0.2442, 95% bootstrap percentile confidence interval (7,900; 19,700) and 5% lower limit 8,400. These results were compared with results that used approximate variance expressions for the estimates of the number of marked whales, the proportion of the population that was marked and population abundance instead of using the bootstrap. The estimates of abundance in 2004 computed for comparison included one based on a modified Petersen estimate of the number of marked whales that omitted the 2005 data as well as the estimate of 12,631 described above. The comparison estimates also included estimates of abundance in 1985 computed from 1984–87 photographic survey data using the same methods. All the abundance estimates computed from photographic data were consistent with expectations based on independent abundance and trend estimates from the ice-based surveys conducted from 1978 to 2001.
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Calambokidis, John, James D. Darling, Volker Deecke, Patrick Gearin, Merrill Gosho, William Megill, Christina T. Tombach, Dawn Goley, Caitlyn Toropova, and Brian Gisborne. "Abundance, range and movements of a feeding aggregation of gray whales (Eschrichtius robustus) from California to southeastern Alaska in 1998." J. Cetacean Res. Manage. 4, no. 3 (May 11, 2023): 267–76. http://dx.doi.org/10.47536/jcrm.v4i3.839.
Full textAbstract:
This study documents the range, abundance and movements of a feeding aggregation of gray whales (Eschrichtius robustus) in the Pacific northwest. Identification photographs were collected by eight collaborating organisations between March and November 1998. Surveys extended between northern California and southeastern Alaska. Effort was variable by region and was concentrated off the northern Washington coast and Vancouver Island. Of 1,242 occasions when suitable photographs of gray whales were obtained in 1998, 155 unique whales were identified. Each individual was photographed an average of 8.0 times (SD = 8.4, range 1-42) and the average tenure of whales seen multiple times was 56 days (SD = 41, range 1-170). Whales seen longer than three months generally were seen in multiple regions. Movements among regions in 1998 were documented for 57 whales with the most frequent interchange among three adjacent areas from northern Washington to central Vancouver Island. The overall pattern of movements among regions was complex; whales were not always moving in the same direction at the same time of year. Movements within 1998 among more distant locations did occur but were less frequently observed. Total distances between resighting positions for individual whales ranged from < 1 to 526 n.miles. Most whales photographed in 1998 had been identified in previous years when compared to photographs collected by some of the collaborators. At least 86 (55%) of the whales identified had been seen previously. The rate of inter-year resightings was highest for whales identified off northern Washington and three areas off British Columbia (from southern Vancouver Island to north of Vancouver Island). In these areas, from 70-100% of the whales seen in each region had been photographed previously. Mark-recapture abundance estimates based on comparisons to samples in 1996 and 1997 were 181 and 179, respectively. The management implication for these whales has become controversial due to the resumption of whaling by the Makah tribe in northern Washington, an area used by both migrating and feeding whales. This research shows that there are a few hundred gray whales that range in summer months from at least northern California to southeastern Alaska. The mechanism by which these animals are recruited into this group and the degree to which they should be managed as a separate unit from the overall population is not resolved.
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Wong, JB, S. Lisovski, RT Alisauskas, W. English, MA Giroux, AL Harrison, D. Kellett, et al. "Arctic terns from circumpolar breeding colonies share common migratory routes." Marine Ecology Progress Series 671 (August 5, 2021): 191–206. http://dx.doi.org/10.3354/meps13779.
Full textAbstract:
The Arctic tern is an iconic seabird, famous for its annual migrations between the Arctic and the Antarctic. Its wide geographical range has impeded knowledge of potential population bottlenecks during its annual bi-hemispheric movements. Although Arctic terns breed in the Pacific, Atlantic, and Arctic coasts of North America, few tracking studies have been conducted on North American Arctic terns, and none in Canada, which represents a significant proportion of their circumpolar breeding range. Using light-level geolocators, we tracked 53 Arctic terns from 5 breeding colonies across a wide latitudinal and longitudinal range within North America. We compared the routes taken by birds in our study and migration timing to those previously tracked from Greenland, Iceland, The Netherlands, Sweden, Norway, Maine (USA), and S. Alaska (USA). Most Arctic terns tracked globally used one of 3 southbound migration routes: (1) Atlantic West Africa; (2) Atlantic Brazil; and (3) Pacific coastal, and one of 2 northbound migration routes: (1) Mid-ocean Atlantic and (2) Mid-ocean Pacific. Some other trans-equatorial seabirds also used these migration routes, suggesting that Arctic tern routes may be important for other species. The migration timing for southbound and northbound migrations was generally different between tracked tern colonies worldwide but generally fell within a 1-2 mo window. Our research suggests that conservation management of Arctic terns during their migration should dynamically adapt with the times of the year that terns use parts of their route. Future identification of common multi-species seabird flyways could aid the international negotiations required to conserve pelagic seabirds such as Arctic terns.
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Livingston, P. A., K. Aydin, J. Boldt, J. Ianelli, and J. Jurado-Molina. "A framework for ecosystem impacts assessment using an indicator approach." ICES Journal of Marine Science 62, no. 3 (January 1, 2005): 592–97. http://dx.doi.org/10.1016/j.icesjms.2004.12.016.
Full textAbstract:
Abstract Assessment of the historical, present, and future states of marine ecosystems and the effects that humans and climate have on the state of an ecosystem are crucial to the scientific advice required to implement an ecosystem-based fishery management system. Management of federal groundfish fisheries in Alaska considers not just the target fishery, but also the possible impact those fisheries might have on other species and the ecosystem. Management actions have ranged from providing protection of endangered species in the region to preventing new fisheries from starting on key foodweb components such as forage fish. A scientific framework for providing ecosystem-based advice that puts the ecosystem first has been evolving over the past few years. This framework provides a way of assessing ecosystem factors that influence target species, the impact the target fishery may have on associated species, and ecosystem-level impacts of fishing. An indicator approach that describes ecosystem status, and trends and measures of human and climate influence has been developed to provide advice to fishery managers. This approach is now being expanded to utilize a variety of models to predict possible future trends in various ecosystem indicators. Future implementation challenges include the refinement of these predictive models, and the inclusion of climate into the models. Identification of sensitive and meaningful ecosystem indicators is also required before a more formalized decision-making process, one that includes ecosystem considerations, can be developed. Most important, the culture of fishery management and research organizations needs to change to embrace the ecosystem-based protections already mandated by various laws.